Use of elexacaftor/tezacaftor/ivacaftor combination in pregnancy

Pregnancy in People With Cystic Fibrosis Treated With Highly Effective Modulator Therapy

With improvements in overall health attributable to newly available medications called highly effective modulator therapy, an increasing number of people with cystic fibrosis (CF) are pursuing pregnancy. However, the safety of these medications for pregnant people with CF and the fetus remains largely unknown. Limited data demonstrate a decline in patients' health and well-being after withdrawal of highly effective modulator therapy during pregnancy; however, both animal and human studies suggest an association between highly effective modulator therapy and cataracts in the offspring that requires further investigation. Use of highly effective modulator therapy can also affect the results of newborn screening and may influence fetal outcomes among fetuses affected by CF as a result of transplacental passage of highly effective modulator therapy. An ongoing prospective cohort study will likely provide more information for pregnant people with CF. Until then, multidisciplinary counseling continues to be critical for people with CF who are of reproductive age.

Therapeutic drug monitoring of elexacaftor, tezacaftor, and ivacaftor before, during, and after pregnancy in women with cystic fibrosis: An observational study

BACKGROUND

Elexacaftor/tezacaftor/ivacaftor (ETI) has improved health and increased life expectancy in many patients with cystic fibrosis (pwCF). Family planning issues have become more important since then. Many women decide to remain on modulator therapy during pregnancy despite insufficient evidence-based recommendations for continuing ETI during pregnancy and lactation.

METHODS

In this retrospective observational report, we present data on maternal serum concentrations of ETI, assessed via a therapeutic drug monitoring (TDM) program established at our CF center for adults. Blood was taken during routine visits. We retrospectively analyzed the corresponding predicted forced expiratory volume in 1 s (ppFEV1), at five time points before, during, and after pregnancy.

RESULTS

Of seven ETI-exposed pregnancies in six women between February 2021 and September 2023, the intake of ETI resulted in no maternal complications and healthy offspring. The dose was reduced in all women, 71.4 % before and 28.6 % during pregnancy, primarily as a result of side effects and/or increased ETI concentrations. Despite dose reductions, serum concentrations showed a broad distribution, with values below, within, and above the Cmax range according to the pharmacokinetic data in the manufacturer's product characteristics. Pulmonary function largely remained stable without pulmonary exacerbations requiring intravenous antibiotic treatment.

CONCLUSION

This observational report shows the most extensive dataset for ETI concentrations during pregnancy. Individualized dose adjustments could help to resolve adverse side effects while continuing CFTR therapy. Specific populations, such as pregnant women, might benefit from a TDM. However, future research with more pharmacokinetic data from pregnant pwCF is needed.

In utero and postnatal ivacaftor/lumacaftor therapy rescues multiorgan disease in CFTR-F508del ferrets

Cystic fibrosis (CF) is caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, with F508del being the most prevalent mutation. The combination of CFTR modulators (potentiator and correctors) has provided benefit to CF patients carrying the F508del mutation; however, the safety and effectiveness of in utero combination modulator therapy remains unclear. We created a F508del ferret model to test whether ivacaftor/lumacaftor (VX-770/VX-809) therapy can rescue in utero and postnatal pathologies associated with CF. Using primary intestinal organoids and air-liquid interface cultures of airway epithelia, we demonstrate that the F508del mutation in ferret CFTR results in a severe folding and trafficking defect, which can be partially restored by treatment with CFTR modulators. In utero treatment of pregnant jills with ivacaftor/lumacaftor prevented meconium ileus at birth in F508del kits and sustained postnatal treatment of CF offspring improved survival and partially protected from pancreatic insufficiency. Withdrawal of ivacaftor/lumacaftor treatment from juvenile CF ferrets reestablished pancreatic and lung diseases, with altered pulmonary mechanics. These findings suggest that in utero intervention with a combination of CFTR modulators may provide therapeutic benefits to individuals with F508del. This CFTR-F508del ferret model may be useful for testing therapies using clinically translatable endpoints.

CFTR dysfunction leads to defective bacterial eradication on cystic fibrosis airways

Dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel by genetic mutations causes the inherited disease cystic fibrosis (CF). CF lung disease that involves multiple disorders of epithelial function likely results from loss of CFTR function as an anion channel conducting chloride and bicarbonate ions and its function as a cellular regulator modulating the activity of membrane and cytosol proteins. In the absence of CFTR activity, abundant mucus accumulation, bacterial infection and inflammation characterize CF airways, in which inflammation-associated tissue remodeling and damage gradually destroys the lung. Deciphering the link between CFTR dysfunction and bacterial infection in CF airways may reveal the pathogenesis of CF lung disease and guide the development of new treatments. Research efforts towards this goal, including high salt, low volume, airway surface liquid acidosis and abnormal mucus hypotheses are critically reviewed.

Unmet challenges in cystic fibrosis treatment with modulators

INTRODUCTION

'Highly effective' modulator therapies (HEMTs) have radically changed the Cystic Fibrosis (CF) therapeutic landscape.

AREAS COVERED

A comprehensive search strategy was undertaken to assess impact of HEMT in life of pwCF, treatment challenges in specific populations such as very young children, and current knowledge gaps.

EXPERT OPINION

HEMTs are prescribed for pwCF with definite genotypes. The heterogeneity of variants complicates treatment possibilities and around 10% of pwCF worldwide remains ineligible. Genotype-specific treatments are prompting theratyping and personalized medicine strategies. Improvement in lung function and quality of life increase survival rates, shifting CF from a pediatric to an adult disease. This implies new studies addressing long-term efficacy, side effects, emergence of adult co-morbidities and possible drug-drug interactions. More sensitive and predictive biomarkers for both efficacy and toxicity are warranted. As HEMTs cross the placenta and are found in breast milk, studies addressing the potential consequences of treatment during pregnancy and breastfeeding are urgently needed. Finally, although the treatment and expected outcomes of CF have improved dramatically in high- and middle-income countries, lack of access in low-income countries to these life-changing medicines highlights inequity of care worldwide.